diff --git a/atlas/additional-guides/environment-variables.mdx b/atlas/additional-guides/environment-variables.mdx
new file mode 100644
index 0000000..48c989b
--- /dev/null
+++ b/atlas/additional-guides/environment-variables.mdx
@@ -0,0 +1,35 @@
+---
+slug: /atlas/additional-guides/environment-variables
+title: Environment Variables
+description: Everything about environment variables
+---
+
+In this guide, you will learn everything about environment variables in Atlas.
+
+## Default variables
+
+Each of the environments has default environment variables that cannot be deleted:
+- `WPE_ATLAS_GIT_PROVIDER`
+- `WPE_ATLAS_REPOSITORY`
+- `WPE_ATLAS` (always true)
+- `WPE_ATLAS_APP_NAME`
+- `WPE_ATLAS_ENV_NAME`
+- `WPE_ATLAS_COMMIT_SHA`
+- `WPE_ATLAS_BRANCH`
+
+These cannot be manually modified, but for example, changing the branch will result in a change of value for `WPE_ATLAS_BRANCH`.
+
+## Custom variables
+
+For each environment separately, you can add, modify, or delete custom environmental variables according to established rules.
+
+The variable cannot be named:
+- `HOME`
+- `PORT`
+- `TMP`
+- `TMPDIR`
+- `TEMP`
+
+The name of variable cannot start with the prefix:
+- `WPE_`
+- `K_`
\ No newline at end of file
diff --git a/atlas/config.json b/atlas/config.json
index eed167f..188da0e 100644
--- a/atlas/config.json
+++ b/atlas/config.json
@@ -167,6 +167,11 @@
           "label": "Password Protection",
           "filePath": "/atlas/additional-guides/password-protection.mdx"
         },
+        {
+          "type": "doc",
+          "label": "Environment Variables",
+          "filePath": "/atlas/additional-guides/environment-variables.mdx"
+        },
         {
           "type": "doc",
           "label": "Support",